Kids who eat food cooked in nonstick pots and pans may have higher levels of LDL cholesterol, a large cross-sectional study found.

Action Points

Point out that crosss-sectional studies cannot determine causality.

Should the relationship be shown to be causal in future studies, it is important to note that there was a nonlinear association between increasing concentrations of PFOA or PFOS and both total cholesterol and LDL, with the largest increases being seen with the lowest levels of PFOA.

Kids who eat food cooked in nonstick pots and pans may have higher levels of LDL cholesterol, a large cross-sectional study found.

At issue are the chemicals used in the manufacture of the cookware -- perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), according to Stephanie J. Frisbee, MSc, of West Virginia University in Morgantown, and colleagues, who report the findings in the September Archives of Pediatrics & Adolescent Medicine.

These two perfluoroalkyl acids are also used for emulsification during manufacturing processes not only of cookware but also of "breathable" and stain-resistant fabrics, carpets, and upholstery materials.

In a community-based sample of young people who were exposed to the chemicals, mean serum concentrations of PFOA and PFOS were 69.2 ng/mL and 22.7 ng/mL, respectively.

Logistic regression determined that higher quintiles of PFOA were positively associated with increased risk of abnormal total cholesterol (adjusted OR 1.2, 95% CI 1.1 to 1.4) and also LDL (OR 1.4, 95% CI 1.2 to 1.7).

Mean total cholesterol in the group was 160.7 mg/dL and mean LDL was 87.3 mg/dL.

Frisbee noted that exposure to PFOA and PFOS also has been documented for food packaging, breast milk, and ambient air, and the median level of PFOA found in the U.S. population at large in 2003 to 2004 was 3.9 ng/mL.

Animal studies showed that the activity of these chemicals is primarily in the liver, and a previous study of adults with environmental exposure found positive associations between PFOA, total cholesterol, and LDL.

To see if lipids also are affected in younger people, Frisbee and colleagues analyzed blood samples from 12,476 subjects ages 1 year to 17.9 years in areas of Ohio and West Virginia where drinking water had been contaminated by a DuPont facility near Parkersburg, W.Va.

Participants' mean age was 11.1 years, and both sexes were equally represented.

More than 95% were white, 39.7% were overweight or obese, and 36.7% reported exercising regularly.

Several different types of analysis were done to explore the association between the chemicals and lipids.

Logistic regression analysis found an adjusted odds ratios for higher quintiles of PFOS of 1.6 (95% CI 1.4 to 1.9) for total cholesterol and 1.6 (95% CI 1.3 to 1.9) for LDL cholesterol.

Higher PFOS quintiles also were associated with a decreased risk of low HDL (OR 0.7, 95% CI 0.6 to 0.9) but neither PFOA nor PFOS was associated with abnormal triglycerides.

Linear model analysis of covariance found that between the first and fifth quintiles of PFOA concentrations there was a 4.6 mg/dL increase in the adjusted mean level of total cholesterol and a 3.8 mg/dL increase in the adjusted mean level of LDL cholesterol.

Corresponding increases for PFOS were 8.5 mg/dL and 5.8 mg/dL.

Further analysis revealed a nonlinear association between increasing concentrations of PFOA or PFOS and both total cholesterol and LDL, with the largest increases being seen with the lowest levels of PFOA, suggesting a saturation effect.

"Across several types of analyses, results consistently provided evidence for a positive association between PFOA and PFOS and serum lipids, specifically an increase in total-C and LDL-C with increasing PFOA and PFOS serum concentrations," the researchers observed.

The hepatic effects of perfluoroalkyl acids in animals are thought to result from peroxisome proliferation, but different or additional mechanisms are likely to be in play for humans, the researchers noted.

Strengths of the study include the size of the sample and the replication of findings from earlier adult studies.

But the cross-sectional nature of the study is a weakness, so causality is uncertain.

Nonetheless, the consistent associations of cholesterol and LDL elevations and serum concentrations of the chemicals seen in this study warrant further investigations, according to the researchers.

"Should the association prove to be etiologic, the cumulative effects of such an elevation in cholesterol on long-term cardiovascular health are unclear given the early age at which these associations were observed," they cautioned.

Participants in the study were part of the C8 Health Project, which was funded by a settlement agreement in the case of Leach v E.I. duPont de Nemours & Co., Civil Action No. 01-C-608.